Pellet fueled grill with cleanout port

ABSTRACT

A pellet-fired grill for barbecue cooking includes a cleanout port in the bottom of the combustion chamber and an access door so that the ash may be cleaned out and removed from the grill without necessitating disassembly of the upper components of the grill. The access door is operated by a pull link, and a stop catch mechanism adjacent to the pull link enables actuation of the pull link assembly only when the stop catch mechanism is released.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.13/345,420, filed Jan. 6, 2012, from which filing date priority isclaimed.

FEDERALLY SPONSORED RESEARCH

Not applicable.

SEQUENCE LISTING, ETC ON CD

Not applicable.

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to barbecue grills and, more particularly, tobarbecue grills that are fueled by pelletized wood byproducts.

Description of Related Art

Most barbecue cookers currently in use are fueled by charcoal orcharcoal briquettes, or employ gas burners fueled by propane orpropane/butane mixtures. However, there are known in the prior artbarbecue cookers that employ pelletized wood byproducts as fuel. Forexample, U.S. Pat. No. 4,823,684 describes a pellet-fired barbecue thatis provided with an automatic pellet feeder to sustain the fire and theongoing cooking task. Starting the fire in the pellet grill is fareasier than in a charcoal grill, and the pellet fuel is cheaper thancharcoal. Moreover, the amount of fuel consumed is only that which isnecessary to complete the cooking task, since the pellet fireextinguishes itself rapidly when the pellet feeder is stopped, whereascharcoal fires tend to burn all the charcoal placed in the grill. And,unlike gas-fired grills, the pellet grill uses wood fuel that producessmoke that flavors the food being cooked on the grill.

However, one of the main problems with existing pellet grills is thatthe ashes left in the burner after use are difficult to remove. If theaccumulated ash is not removed regularly, it may adversely affect theability to start the pellet burner of the grill. Indeed, the burnershould have the ash removed prior to each lighting of the grill.

Prior art pellet-fired grills are not well-constructed to facilitateremoval of the ash from the burner unit. Generally, the upper grillcomponents must be disassembled to gain access to the burner. Forexample, the cooking grates must be removed, an aversive process due tothe grease and soot that inevitably coats the grates. Then the heatdeflector and flame distributor must be removed to expose the burnerunit. The ashes may then be removed, using a vacuum cleaner, and theheat deflector, flame distributor, and cooking grates must be replaced.This is a messy, dirty, and difficult process to undertake every timethe grill is used.

BRIEF SUMMARY OF THE INVENTION

The present invention generally comprises a pellet-fired grill forbarbecue cooking. A salient feature of the grill is that is providedwith a cleanout port in the bottom of the grill that enables access tothe ash that falls from the burner unit, so that the ash may be cleanedout and removed from the grill without necessitating disassembly of theupper components of the grill.

The grill is comprised of a base that supports a pan section at a heightthat is appropriate for the cooking task. The pan section includes oneor more cooking grates supported above a pellet burner assembly. Theburner assembly typically includes a combustion box that is fed pelletfuel by an auger or other transport arrangement, and a flame distributordisposed above the combustion box to spread the flame generated by theburning fuel. A heat deflector may also be provided, disposed above theflame distributor to spread the heat to the entire grill area. One ormore cooking grates are removably disposed above the heat deflector tosupport food while it is cooked on the grill. Typically, a grill coveris hingedly secured to the pan section to enable open grilling or closedroasting/grilling of comestibles. These enumerated components aretypical of prior art pellet-fired cooking grills.

The invention provides an ash cleanout opening in the bottom panel ofthe pellet burner assembly, and an access door slidably secured adjacentto the cleanout opening. The door may be connected to a knob or pulllink so that it may be slidably translated longitudinally to open andclose the cleanout opening. In the closed position the access doorsubstantially seals the cleanout opening so that the airflow through theburner assembly is not disrupted from its designed path. When the accessdoor is opened the ash accumulated in the burner may fall out of theburner and be collected. If there is a lower heat deflector or panel ofthe grill construction, it is provided with an opening directlysubjacent to the access door, so that the ash will fall through thesubjacent opening and be collected in a bucket or similar container forproper disposal.

In alternative embodiments the access door may be hinged to the bottomof the burner assembly adjacent to the cleanout opening, or may bearranged to pivot about a pin or shaft to open or block the cleanoutopening.

A further embodiment of the invention provides a stop catch mechanismthat prevents unintended or accidental actuation of the pull link. Asliding bracket is mounted on the grill adjacent to the point where thepull link extends from the grill, the bracket including a clevis-likeslot that engages an annular recess provided on the pull link rodadjacent to the outer knob. The bracket must be slidably disengaged fromthe pull link rod before the knob may be translated to open the accessdoor, thereby eliminating inadvertent opening of the access door.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective front view of the pellet-fueled grill of thepresent invention.

FIG. 2 is a cutaway perspective view of the burner assembly of the grillof FIG. 1, showing the access door portion of the invention.

FIG. 3 is a side cross-sectional elevation of the burner assembly ofFIG. 2, showing the access door in the closed disposition duringcombustion.

FIG. 4 is a side cross-sectional elevation of the burner assembly ofFIGS. 2 and 3, showing the access door in the closed position with ashaccumulation after use.

FIG. 5 is a side cross-sectional elevation of the burner assembly ofFIGS. 2-4, showing the access door in the open position for removal ofaccumulated ash.

FIG. 6 is a cutaway perspective view as in FIG. 2, showing a furtherembodiment of the access door portion of the invention.

FIG. 7 is a cutaway perspective view as in FIGS. 2 and 5, showinganother embodiment of the access door portion of the invention.

FIG. 8 is a plan view of a further embodiment of the pull link assemblyof the invention.

FIGS. 9 and 10 are enlarged perspective views showing the stop catchmechanism of the invention in the latched and unlatched dispositions,respectively.

DETAILED DESCRIPTION OF THE INVENTION

The present invention generally comprises a pellet-fired grill forbarbecue cooking that provides a cleanout port in the bottom of thegrill to enable access to the ash that falls from the burner unit, sothat the ash may be cleaned out and removed from the grill withoutnecessitating disassembly of the upper components of the grill.

With regard to FIG. 1, the pellet-fired grill 11 employs some componentsknown in the prior art and shown here to elucidate the form andfunctions of the invention. The grill 11 includes a base 12 having arectangular solid form and including a storage cupboard 13 behind doors14. A pan section 16 rests atop the base 12 and houses theheat-generating components of the grill. One or more grates 17 areremovably secured at the top of the pan section support food items beinggrilled. A supply bin 18 of pellet fuel is disposed adjacent to the pansection 16, and a pellet transport device such as an auger is disposedbetween the bin 18 and a pellet burner assembly 21. A grill cover 22 ishinged at one edge to the pan section 16 to enable open grill cooking aswell as closed grill roasting.

With reference to FIG. 2, the pellet burner assembly 21 generallyincludes a combustion chamber 23 secured within a coffer-like housing24. Supported on the housing 24 is a lower heat deflector 46 and, abovethat, the upper heat deflector 47. A bottom heat deflector 48 is spacedbelow the combustion chamber 23, and is provided with a bottom opening49 extending therethrough. The combustion chamber 23 includes a cup 26that receives the pellets of fuel delivered by a transport mechanism toan auger tube or chute 27, whereby the pellets to be directed by thechute 27 into the cup 26, where they are burned. Note that combustionair is blown through the housing 24, which feeds air through holes 25 inthe cup 26 to burn the pellets therein. The combustion chamber 23 has anopen top and a bottom opening 32, with an access door 33 disposed at itsbottom end in sealing fashion, so that pellets of fuel are retained andburned in the cup 26 during operation of the grill, as shown in FIG. 3.Over time the combustion process generates ash that forms in the cup 26and tends to collect therein, as shown in FIG. 4.

The access door 33 includes opposed longitudinal sides, and the bottomof the combustion chamber 23 includes supports 35 (FIGS. 3-5) thatengage the longitudinal sides and enable the door to translatelongitudinally in slidable fashion. The door 33 is dimensioned to spanthe width of opening 32 so that the opening is entirely occluded andblocked. Note that the opening 32 in the bottom of the combustionchamber 23 is aligned with the opening 49 in the bottom heat deflector48.

A pull link 41 is connected to the door 33 and disposed to extendlongitudinally. The link 41 protrudes from the front or side or back ofthe grill assembly, and terminates in a handle or knob 42. The knob 42enable a user to slide the door in the longitudinal direction out of itsblocking position in opening 32. When the door is pulled free of theopening 32 the ash that has accumulated in the cup 26 is free to fallthrough the opening 32 and through the opening 49 in the bottom heatdeflector, to be collected in a disposal container such as bucket 40(FIG. 1). The door 33 is translated inwardly to reclose the slotopening. This closure preserves the combustion air flow pattern withinthe combustion chamber. The opening 32 may also be used to admit avacuum intake hose from a vacuum cleaning device to positively removethe ash from the combustion chamber 23 and holes 25.

With regard to FIG. 6, there is shown a further embodiment in which thecomponents of the burner assembly 21 are substantially similar to thoseof FIGS. 2-5 and are accorded the same reference numerals. In thisembodiment the access door 33A is secured to the housing 24 by hinge 44,so that the door 33A may pivot open as explained previously to removeaccumulated ash, and to pivot closed to block opening 32A. The hingeddoor 33A is connected to a link 41A which extends longitudinally throughthe front panel of the grill and through an arcuate slot 51 as shown inFIG. 6. A user may push the link 41A to translate along the slot 51 torotate the door 33A between the open and closed positions, so that thecombustion chamber may be cleared of ash when needed, and then closedfor further operation.

With reference to FIG. 7, there is shown a further embodiment in whichthe components of the burner assembly 21 are substantially similar tothose of FIGS. 2-5 and are accorded the same reference numerals. In thisembodiment the access door 33B is secured to the bottom panel of housing24 by a pivot pin 45 extending through one corner portion of the door33B, whereby the door may rotate about the pin 45 from the open to theclosed position. As before, the hinged door 33B is connected to a pulllink 41B as shown in FIG. 7 to enable rotation of the door 33B about thepin 45 to accomplish opening and closing of the access door as explainedin the foregoing.

It should be noted that the description of the use of the access door33-33B does not mention any task involving disassembly of the uppergrill components in the pan section 16, such as the grate(s) 17, flamespreader, or heat deflector. Thus the access door alleviates a greatamount of messy, aversive work required to clean ash out of prior artpellet-fired grills.

With regard to FIGS. 2 and 8-10, a further aspect of the inventioncomprises a stop catch mechanism 51 that is secured to a sidewall 50 ofthe grill superjacent to the point where the pull link 41 protrudes fromthe sidewall 50, which may be at the front or side or rear of theassembly. It has been noted that opening the door 33 during operation ofthe grill may be dangerous, particularly since the combustion chambercontains the positive pressure of the blower as well as hot embers andash debris at the bottom thereof. If the handle 42 is pulledaccidentally, as by a passerby, an inexperienced grill operator, ormalicious mischief, the ash and embers may be blown all over the nearbyarea and the persons occupying it.

The stop catch mechanism 51 includes a plate 52 extending parallel tothe sidewall 50 of pan section 16, and a finger tab 53 extendingoutwardly and generally orthogonally from the plate 52 at the upper edgethereof. A pair of screw slots 54 extend generally vertically andparallel at opposed ends of the plate 52, and screws 56 extend throughthe slots 54 and are anchored in the sidewall 50, enabling the mechanism51 to slide vertically through a limited excursion. Extending outwardlyfrom a central portion of the lower edge of the plate 52 is an archedprojection 57 having a central clevis opening 58. As shown best in FIG.10, the clevis opening 58 is a downwardly opening slot having opposedside edges joined by a smoothly curved interior edge.

With particular reference to FIG. 8, the pull link 41 describedpreviously is modified with the addition of an annular detent recess 43disposed adjacent to the stem end of pull knob 42. The detent recess 43may be defined by a bushing 44 assembled to the pull rod 41 adjacent tothe stem end of the knob, or the recess 43 may comprise an annulargroove that is milled, turned, molded, printed, or otherwise formed bywell known manufacturing processes. The annular detent recess isdimensioned and disposed to be engageable by the clevis opening 58 ofstop catch mechanism 51. As shown in FIG. 9, the stop catch mechanism istypically disposed in a downward position with the clevis opening 58engaged with the detent recess 43 in complementary fashion, thuspreventing the knob 42 from being pulled outwardly to open the accessdoor 33. Thus accidental opening of the combustion chamber while in useis prevented.

To open the access door 33 when the grill is turned off and cool, theuser must first slide the mechanism 51 upwardly by engaging the fingertab 53, thus releasing the clevis opening 58 from the detent recess 43.The user may then easily pull the knob 42 to dump the accumulated ashfrom the combustion chamber, as described previously. After the ashdisposal process, the finger tab 53 may be used to push the mechanism 51downwardly to re-engage the detent recess 43 and establish the detentedposition as an ongoing safety precaution.

It is noted that the mechanism 51 may be applied to all the embodimentsdescribed above, such as those of FIGS. 6 and 7 without departing fromthe spirit and teachings of this invention.

The foregoing description of the preferred embodiments of the inventionhas been presented for purposes of illustration and description. It isnot intended to be exhaustive or to limit the invention to the preciseform disclosed, and many modifications and variations are possible inlight of the above teaching without deviating from the spirit and thescope of the invention. The embodiment described is selected to bestexplain the principles of the invention and its practical application tothereby enable others skilled in the art to best utilize the inventionin various embodiments and with various modifications as suited to theparticular purpose contemplated. It is intended that the scope of theinvention be defined by the claims appended hereto.

The invention claimed is:
 1. In a cooking grill that has a grate forsupporting food to be cooked and a pellet fuel combustion unit beneaththe grate with a combustion housing supporting a combustion chamberwhere pellet fuel is burned to ash, the improvement comprising: anaccess opening formed in a bottom panel of said combustion chamber, saidaccess opening disposed substantially directly beneath said combustionchamber; an access door dimensioned to entirely close said accessopening; a pull link assembly for moving said access door from a firstposition in which said access opening is blocked to a second position inwhich said access opening is open to allow accumulated ash in saidcombustion chamber to fall therethrough; a stop catch mechanismreleasably engaging said pull link assembly to enable actuation of saidpull link assembly only when said stop catch mechanism is released; saidpull link assembly including a pull rod extending from said access doorin said longitudinal direction, and a knob secured to a distal end ofsaid pull rod; said pull rod protruding from a sidewall of said cookinggrill, said stop catch mechanism being secured to said sidewall adjacentto said pull rod; said stop catch mechanism including a plate having aclevis opening adjacent to said pull rod, and an annular detent recessformed on said pull rod and disposed to be engaged by said clevisopening.
 2. The improved cooking grill of claim 1, wherein said plateincludes at least one slot extending therethrough to receive a fasteneranchored in said sidewall of said cooking grill, said plate beingslidable along said at least one slot.
 3. The improved cooking grill ofclaim 2, wherein said at least one slot is oriented to enable said plateto slide reciprocally and engage or disengage said annular detent recesswith said clevis opening.
 4. The improved cooking grill of claim 3,further including a finger tab extending generally outwardly from saidplate to enable manual engagement of said stop catch mechanism.